Heater for lubricating oil



C. R. SHORT HEATER FOB LUBRICATING OIL Filed Feb. 13, 1926 April 2, 1929.

ll B $0 Patented Apr. 2, 1929.

UNITED STATES PATENT oFFicE.

CHARLES R. SHORT, OF DAYTON, OHIO, ASSIGNOR TO GENERAL MOTORS RESEARCH CORPORATION, OF DETROIT, MICHIGAN, A CORPORATION OF DELAWARE.

HEATER FOR LUBRICATING OIL.

Application filed February 5 It has heretofore been proposed to provide heaters for the lubricating oil used in automobile engines so as to insure that during winter operation the oil may be quickly rendered sufliciently viscous to properly lubricate the moving parts. Such heaters also have, as a secondary object, the thawing out of theoi'l sludge which-collects about the filtering screens and lodges in the oil pump interfering with proper functioning of the oil circulating system. It has also been found desirable in connection with systems of crankcase ventilation wherein diluents are removed from theoil by the evaporative action resulting from the passage of considerable volumes of air through the crankcase to provide means for heating the oil so that the temperature of the latter will be at a point where evaporation readily takes place.

The heater which is the subject matter of this application is adapted to serve all of the purposes above mentioned. In addition, it is characterized by a control for the heating medium permitting the regulation of the de-' gree of heating and permitting the application of heat to be practically shut off durin summer operation. It is also characterize by the fact that the conduit which carries the heating medium into contact withthe oil is provided with an extended surface facilitating the conduction of heat to the oil and at the same time assisting materially in preventing the walls of the conduit from reaching such a high temperature as to cause decomposition orcharring of the lubricant. The specific design is characterized by simplicity and low cost of construction adapting it very well for commercial production.

In the drawings:

Figure 1 is an elevation of a portion of the crankcase of an internal combustion engine, parts being broken away to show the details of my heater.

Figure 2 is a view taken on line 22 of Figure 1.

Figure 3 Figure 1. 1

The reference character 2 indicates a lubricant receptacle, in this case the conventional crankcase of an internal combustion engine. I have indicated at 4 the oil pump which, in the type of engine illustrated, is immersed in the lubricant. The reference character 6 indicates a conduit carrying an is a view taken on line 3-3 of 13, 1926. Serial No. 88,112.

engine heated medium,'this conduit in the present instance connecting the exhaust manifold to the, usual muflier.

My improved heater is connected in parallel with a portion of the conduit 6 and comprises an inlet 8 and an outlet 10 connected withinthe crankcase by a flattened conduit 12. It is apparent from the drawing that the inlet and outlet are of identical construction and comprise tubular members connected to the exhaust conduit by suitable couplings indicated at 14 and having their inner ends closed. These tubular members are provided with longitudinally extending slots 16 to the edges of which the ends of the flattened tubular member 12 are secured by welding or soldering.

, I have provided means in the conduit 6 for controlling the diversion of exhaust gases through the heater. In its simplest form this means consists of a butterfly valve 20 extending across the conduit 6 between the inlet 8 and the outlet 10. It is apparent that the quantity of exhaust gases passing through the heater will vary in accordance with the position of the valve, and in the full open position of the valve practically none of the gases will pass through the heater. I have indicated no specific form of operating means for the valve. It is apparent that it may be manually controlled, may be controlled by a thermostat which in turn is governed by the temperature of the lubricating oil, or may be connected to the intake mixture heat control customarily a part of the standard equipment of various makes of automobiles of which the Buick may be regarded as a typical example.

The large surface area of the portion 12 of the heater facilitates passage of heat from the exhaust gases to the oil andalso has the desirable effect that the maximum tempera ture of the walls of the heater is reduced so that the oil is less likely to be heated to an extent which would produce decomposition or charring.

I claim:

1. An internal combustion engine having a crankcase serving as a receptacle for'lubricant, a heater for said lubricant comprising an inlet conduit and an outlet conduit for a heating medium projecting into said receptacle, and having their inner ends closed, said conduits being provided with lateral openings, and a conduit connecting said lateralopenings, said conduit being of extended flattened shape to present a large area for contact with the oil to facilitate heating of the same.

2. An internal combustion engine having a crankcase serving as a lubricant reservoir, and an exhaust conduit, branch conduits extending from said exhaust conduit into the crankcase and having their inner ends closed, said branch conduits being provided with apertures in their side Walls elongated. longitudinally thereof, and a conduit extending between said branch conduits and establishing communication between said apertures, and a valve in said first named conduit between the branches thereof.

3. The combination of a lubricant reservoir and a heater therefor comprising a pair of spaced conduits extending into said reservoir, said conduits being provided with elongated apertures, and a conduit extending between said first named conduits and establishing communication between said apertures, said conduit being extended transversely to provide an extended area for contact with thelubricant to promote heating'thereof; In testimony whereof I aflix my signature. CHARLES R. SHORT. 

